What I am intending to do is…
:?: Take plug socket from wall and wire up 2.5mm swa cable to it.(socket is a double that always has two plugs pluged in to it).then run swa cable 12 meters to shed and wire it to isolation switch.isolation switch is wired to consumer unit. I have wired a 3kw water heater and a 300watt water pump to a 32amp mcb,(protected)in consumer unit.also a 300 watt air blower to 6 amp mcb in unit,these are rccb (rcd)proteted.i also want to wire up 4 double plug sockets,(on a loop/OR SPUR),coming from and going back to consumer unit into a 6amp or 32 amp mcb(not protected).the only thing that will ever be pluged into sockets is 12v transformers for garden lighting.IS IT OK TO DO THIS?
:?: thanks for reading.

Hi, I'm a bit confused after reading this, as I was considering a similar option and thought I'd read elsewhere on the site that you could add a spur to a ring main to provide the power. I have a standalone small shed (3m from house) within which I'm intending to put a small fridge and a couple of sockets for plugging in the mower/power drill. I intended to put in a Consumer Unit in the shed with RCD and fuses for the sockets and lighting.

This type of work should be done by a qualified electrician that is ideally a member of the competant persons scheme, this means thier work should be in compliance to that of document p of the building regulations or be notified to your local building controls officer.
Lots of things to be considered and safety is paramount.
KB

rosebery,
Any chance you could clarify a couple of points:
You said "should be a new circuit at the consumer unit". Could you point me to where in the 17th this is specified. Why should a shed circuit not be supplied from a ring main via a combined RCD/fused spur (assuming not more than 13A total load is needed).
You said "An RCD is not the same thing as an RCCB." Could you explain the difference. When what we now call RCDs were first introduced they were called RCCBs, is there now a distinction between the two.
Thanks for your help.
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